rtc-pcap.c

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/*
 *  pcap rtc code for Motorola EZX phones
 *
 *  Copyright (c) 2008 guiming zhuo <[email protected]>
 *  Copyright (c) 2009 Daniel Ribeiro <[email protected]>
 *
 *  Based on Motorola's rtc.c Copyright (c) 2003-2005 Motorola
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License version 2 as
 *  published by the Free Software Foundation.
 *
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/mfd/ezx-pcap.h>
#include <linux/rtc.h>
#include <linux/slab.h>
#include <linux/platform_device.h>

struct pcap_rtc {
    struct pcap_chip *pcap;
    struct rtc_device *rtc;
};

static irqreturn_t pcap_rtc_irq(int irq, void *_pcap_rtc)
{
    struct pcap_rtc *pcap_rtc = _pcap_rtc;
    unsigned long rtc_events;

    if (irq == pcap_to_irq(pcap_rtc->pcap, PCAP_IRQ_1HZ))
        rtc_events = RTC_IRQF | RTC_UF;
    else if (irq == pcap_to_irq(pcap_rtc->pcap, PCAP_IRQ_TODA))
        rtc_events = RTC_IRQF | RTC_AF;
    else
        rtc_events = 0;

    rtc_update_irq(pcap_rtc->rtc, 1, rtc_events);
    return IRQ_HANDLED;
}

static int pcap_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
{
    struct platform_device *pdev = to_platform_device(dev);
    struct pcap_rtc *pcap_rtc = platform_get_drvdata(pdev);
    struct rtc_time *tm = &alrm->time;
    unsigned long secs;
    u32 tod;    /* time of day, seconds since midnight */
    u32 days;   /* days since 1/1/1970 */

    ezx_pcap_read(pcap_rtc->pcap, PCAP_REG_RTC_TODA, &tod);
    secs = tod & PCAP_RTC_TOD_MASK;

    ezx_pcap_read(pcap_rtc->pcap, PCAP_REG_RTC_DAYA, &days);
    secs += (days & PCAP_RTC_DAY_MASK) * SEC_PER_DAY;

    rtc_time_to_tm(secs, tm);

    return 0;
}

static int pcap_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
{
    struct platform_device *pdev = to_platform_device(dev);
    struct pcap_rtc *pcap_rtc = platform_get_drvdata(pdev);
    struct rtc_time *tm = &alrm->time;
    unsigned long secs;
    u32 tod, days;

    rtc_tm_to_time(tm, &secs);

    tod = secs % SEC_PER_DAY;
    ezx_pcap_write(pcap_rtc->pcap, PCAP_REG_RTC_TODA, tod);

    days = secs / SEC_PER_DAY;
    ezx_pcap_write(pcap_rtc->pcap, PCAP_REG_RTC_DAYA, days);

    return 0;
}

static int pcap_rtc_read_time(struct device *dev, struct rtc_time *tm)
{
    struct platform_device *pdev = to_platform_device(dev);
    struct pcap_rtc *pcap_rtc = platform_get_drvdata(pdev);
    unsigned long secs;
    u32 tod, days;

    ezx_pcap_read(pcap_rtc->pcap, PCAP_REG_RTC_TOD, &tod);
    secs = tod & PCAP_RTC_TOD_MASK;

    ezx_pcap_read(pcap_rtc->pcap, PCAP_REG_RTC_DAY, &days);
    secs += (days & PCAP_RTC_DAY_MASK) * SEC_PER_DAY;

    rtc_time_to_tm(secs, tm);

    return rtc_valid_tm(tm);
}

static int pcap_rtc_set_mmss(struct device *dev, unsigned long secs)
{
    struct platform_device *pdev = to_platform_device(dev);
    struct pcap_rtc *pcap_rtc = platform_get_drvdata(pdev);
    u32 tod, days;

    tod = secs % SEC_PER_DAY;
    ezx_pcap_write(pcap_rtc->pcap, PCAP_REG_RTC_TOD, tod);

    days = secs / SEC_PER_DAY;
    ezx_pcap_write(pcap_rtc->pcap, PCAP_REG_RTC_DAY, days);

    return 0;
}

static int pcap_rtc_irq_enable(struct device *dev, int pirq, unsigned int en)
{
    struct platform_device *pdev = to_platform_device(dev);
    struct pcap_rtc *pcap_rtc = platform_get_drvdata(pdev);

    if (en)
        enable_irq(pcap_to_irq(pcap_rtc->pcap, pirq));
    else
        disable_irq(pcap_to_irq(pcap_rtc->pcap, pirq));

    return 0;
}

static int pcap_rtc_alarm_irq_enable(struct device *dev, unsigned int en)
{
    return pcap_rtc_irq_enable(dev, PCAP_IRQ_TODA, en);
}

static const struct rtc_class_ops pcap_rtc_ops = {
    .read_time = pcap_rtc_read_time,
    .read_alarm = pcap_rtc_read_alarm,
    .set_alarm = pcap_rtc_set_alarm,
    .set_mmss = pcap_rtc_set_mmss,
    .alarm_irq_enable = pcap_rtc_alarm_irq_enable,
};

static int __devinit pcap_rtc_probe(struct platform_device *pdev)
{
    struct pcap_rtc *pcap_rtc;
    int timer_irq, alarm_irq;
    int err = -ENOMEM;

    pcap_rtc = kmalloc(sizeof(struct pcap_rtc), GFP_KERNEL);
    if (!pcap_rtc)
        return err;

    pcap_rtc->pcap = dev_get_drvdata(pdev->dev.parent);

    platform_set_drvdata(pdev, pcap_rtc);

    pcap_rtc->rtc = rtc_device_register("pcap", &pdev->dev,
                  &pcap_rtc_ops, THIS_MODULE);
    if (IS_ERR(pcap_rtc->rtc)) {
        err = PTR_ERR(pcap_rtc->rtc);
        goto fail_rtc;
    }


    timer_irq = pcap_to_irq(pcap_rtc->pcap, PCAP_IRQ_1HZ);
    alarm_irq = pcap_to_irq(pcap_rtc->pcap, PCAP_IRQ_TODA);

    err = request_irq(timer_irq, pcap_rtc_irq, 0, "RTC Timer", pcap_rtc);
    if (err)
        goto fail_timer;

    err = request_irq(alarm_irq, pcap_rtc_irq, 0, "RTC Alarm", pcap_rtc);
    if (err)
        goto fail_alarm;

    return 0;
fail_alarm:
    free_irq(timer_irq, pcap_rtc);
fail_timer:
    rtc_device_unregister(pcap_rtc->rtc);
fail_rtc:
    platform_set_drvdata(pdev, NULL);
    kfree(pcap_rtc);
    return err;
}

static int __devexit pcap_rtc_remove(struct platform_device *pdev)
{
    struct pcap_rtc *pcap_rtc = platform_get_drvdata(pdev);

    free_irq(pcap_to_irq(pcap_rtc->pcap, PCAP_IRQ_1HZ), pcap_rtc);
    free_irq(pcap_to_irq(pcap_rtc->pcap, PCAP_IRQ_TODA), pcap_rtc);
    rtc_device_unregister(pcap_rtc->rtc);
    kfree(pcap_rtc);

    return 0;
}

static struct platform_driver pcap_rtc_driver = {
    .remove = __devexit_p(pcap_rtc_remove),
    .driver = {
        .name  = "pcap-rtc",
        .owner = THIS_MODULE,
    },
};

static int __init rtc_pcap_init(void)
{
    return platform_driver_probe(&pcap_rtc_driver, pcap_rtc_probe);
}

static void __exit rtc_pcap_exit(void)
{
    platform_driver_unregister(&pcap_rtc_driver);
}

module_init(rtc_pcap_init);
module_exit(rtc_pcap_exit);

MODULE_DESCRIPTION("Motorola pcap rtc driver");
MODULE_AUTHOR("guiming zhuo <[email protected]>");
MODULE_LICENSE("GPL");